Condensation product of nuclear alkyl-substituted hydroxyaromatic compound



Patented Jan.30, 1945 CONDENSATION PRODUCT OF NUCLEAR ALKYL- SUBSTITUTED HYDROXYABO- MATIC COMPOUND Orland M. Reiii', Woodbury, N. L, asaignor to Sooony-Vacuum Oil Company,

Incorporated,

New York, N. Y., a corporation of New York No Drawing. Application March 12, 1942, Serial No. 434,329

This invention relates to the production of certain new chemical compounds or compositions which may be generally designated as the sulfides, selenides or tellurides (generically hereinafter sometimes referred to as sulf-selene-telides) of the esters of nuclear alkyl-substituted hydroxyaromatic compounds and preferably the inorganic acid esters (acyls) of such hydroxyaromatic compounds. These compositions may also be generally designated-as the sulfides, selenides or tellurides of acyloxyaromatic (or aroxyacyl) compounds, preference being given to such compounds in which the acyl group corresponds to an oxy-inorganic acid (such as phosphorous acid).

In other words, the compounds of the present invention are nuclear alkyl-substituted aromatic sulfides, selenides, or tellurides characterized by the presence of an aromatic nucleus having a nuclear hydrogen replaced by an ester (oxy-acyl) group. The preferred compounds of the present invention comprise those of the above general class in which the alkyl-substituent or group is a heavy alkyl group of not less than twenty carbon atoms. Another and more specifically preferred product of the present invention comprises an intimate mixture of compounds falling within the above general class wherein the characterizing acyl groups and also the divalent elements mentioned above are the same and wherein the alkyl substituents in said compounds are attached to the aryl nuclei and consist essentially of hydrocarbon radicals corresponding substantially to the different aliphatic hydrocarbons contained in paraflin wax. This preferred product is hereinafter referred to as a wax"-substituted compound (of the above general class).

With respect to the above mentioned heavy alkyl-substituted or wax-substituted compounds or compositions of the present invention, further preference is given within this group to those which are soluble in or miscible with mineral oil.

The compositions of the present invention are considered to be condensation products wherein two or more of the aromatic nuclei of the characterizing acyloxyaromatic groups are presumably-interconnected through a linkage (or linkages) comprised of an element selected from the group consisting of sulfur, selenium and tellurium, preference being given to sulfur. Through the introduction of sulfur, for example, in the manner or manners to be hereinafter described,

I obtain what may be broadly termed a sulfide of an aroxy-acyl.

My preference for the above mentioned 011- that they are of multifunctional activity, when blended with viscous mineral oil fractions in that they eifect improvement of several unrelated and related properties of the 011. For example, this preferred oil-miscible group of compounds or compositions coming within the general field of invention contemplated herein are effective, when blended in a minor proportion with mineral oil fractions of the lubricant type, to depress the pour point, improve the viscosity index (V. I.),

and inhibit oxidation of the oil. By inhibiting oxidation these oil-miscible compositions act to retard the formation of sludge and acidic products of oxidation. They also have a peptizing action on such sludge as may eventually be formed. Thus, any one of these preferred oilmis'cible compounds or compositions may, for example, be used in internal combustion engine lubricants to retard or prevent the sticking of piston rings or prevent the corrosion of bearings, particularly those formed of alloy metals normally susceptible to corrosion, etc., and at the same time it will act to depress the pour point and improve the viscosity index of the oil.

It should be understood that the use of these preferred oil-miscible compounds or compositions is not confined to lubricating oils, but they may be employed in any mineral oil fractions where one or more of the improved properties. recited above is desired. In this regard it is to be further understood that the present invention is not concerned with mineral oilcompositions containing these preferred oil-soluble compounds, such oil compositions forming the subject matter of my copending application Serial No. 331,230, filed April 23, 1940, to which reference is made for further details in the composition of these compounds.

It is also to be understood that while my invention contemplates oil-miscible compounds or compositions of the type above referred to as a preferred class or group within the general field of invention, the invention is not limited to such oil-miscible compounds or compositions, since this whole class of new materials is possessed of, valuable properties irrespective of oil-miscibility. For example, these compoundsor compositions may be used as intermediaries in the production of resins, resin-like materials; rubber substitutes, etc. Certain of the compositions possess valuable pharmaceutical, insecticidal or similar properties due to the presence of particular substituents such for instance as a'particular acyl or residual hydroxyl group. Numerous other uses of the compositions contemplated herein will be apparent to those skilled in the art from the following description of their compositions and methods of synthesis.

As previously pointed out the preferred compounds or compositions contemplated by this invention are characterized by the fact that at least one replaceable hydrogen on the aromatic nucleus is substituted with an aliphatic hydrocar bon radical or group characteristic of an aliphatic hydrocarbon of high molecular weight which we may term a heavy alkyl group. For obtaining the preferred group of compounds or compositions which are miscible with mineral oil and which possess the multifunctional oil-improving properties, we have found that this heavy alkyl" substituent in the acyloxyaromatic compounds under discussion must be derived from a predominantly straight chain aliphatic hydrocarbon of at least twenty carbon atoms such as characterize crystalline petroleum wax. As a matter of fact, petroleum wax is considered to be a preferred source of the "heavy alkyl substituent and it is for that reason that the compounds or compositions described herein are referred to as wax-substituted." It is to be understood, however, that'the term "wax" as used herein is applied in a broad sense and is intended to include any pure compound or mixture of compounds predominantly aliphatic in nature and containing at least twenty carbon atoms which is susceptible of attachment to an aromatic nucleus to provide a substituent which, in the proper proportions, will impart to the characterizing aroxyacyl sulfide (or selenide or telluride) group or nucleus the multifunctional oil-improving properties referred to.

In the preferred group of compounds or compositions contemplated herein, which are oilmiscible and which by virtue of their heavy alkyl (wax) substituent have multifunctional properties in mineral oil blends, it is important that the heavy alkyl (wax) substituent comprise a substantial proportion of the composition or compound as a whole. This will be discussed in detail later in the specification.

In addition to the heavy alkyl (wax) substit: uent the compounds or compositions contemplated herein may have additional nuclear hydrogen replaced with other substituents which in the case of the preferred oil-miscible compositions may or may not have a solubilizing effect upon the composition as a whole. For example, part of the nuclear hydrogen may be substituted with a radical selected from the group consisting of: aliphatic hydrocarbon groups having less than twenty carbon atoms, hydroxyl, ester. xanthate, alkyl sulfide. aryl sulfide, keto, alkoxy, aroxy, aldehyde, oxime, aralkyl, aryl, alkaryl, halogen, nitroso, N-thio, N-acyl, cyano and (--H2) formed by hydrogenation. Compounds of the above general formula-type are illustrated by the following specific formula:

in which at least one of the R's represents an aliphatic radical or group, containing at least twenty carbon atoms and in which the remaining R's represent residual hydrogen which may be replaced with a radical selected from the group aseasae consisting of: aliphatic groups containing less than twenty carbon atoms, hydr'oxyl, ester, xanthate, alkyl, sulfide, aryl sulfide, keto, alkoxy, aroxy, aldehyde, oxime, aralkyl, aryl, alkaryl, halogen, nitroso, N-thio, N-acyl, cyano and (-112) formed by hydrogenation; and in which Ac represents an acyl group; and in which X represents a divalent element selected from the groups consisting of sulfur, selenium and tellurium, and n represents the number of such divalent elements, from one to four or more; and in which the hexagonal ring represents a mono-, dior tri-cyclic aromatic nucleus.

It will be understood of course that where the number of divalent elements (represented by X in the above formula) is greater than one they form a chain" of such elements which are interconnected among themselves.

It will also be understood that since the condensation reaction (hereinafter described) which is employed in synthesizing the sulfides. etc., contemplated herein, is presumably attended by a certain amount of multiple condensation, such further condensed compounds, herein called polymers, are included herein within the terms sulfides, etc., and as coming within the general formula above. The general formulae corresponding to the polymers of this character will be readily understood from the above by those skilled in the art.

It is pointed out further that the term sulflde, as used herein, is inclusive of the monosulfides, disulfldes, trisulfides, tetrasulfldes, etc.; that is, it includes both monosulfides and poly sulfides and the corresponding rule applies to the terms selenide and telluride."

It will be understood that the compounds or compositions contemplated by this invention may be pure compounds satisfying the conditions enumerated above with any one ofthe various monoor polycyclic aromatic nuclei in the characterizing nuclear group. However, in manufacturing the preferred composition by the preferred procedure, as will appear later on, the final product obtained is normally or usually a mixture of different compounds the individual characteristics of which differ in their alkyl substituents (according to the different aliphatic hydrocarbons in an alkylating material such as paraflln wax) in the number of alkyl substituents on the characterizing nucleus and in the number of nuclei attached to a single long chain alkyl group. For further details in the composition of such mixtures of compounds reference is made to my aforesaid application Serial Number 331,230, filed April 23, 1940.

As aforesaid, it is important that the "waxsubstituted compounds of the present invention which are preferred for use as oil-improving agents have the aryl nucleus substituted with heavy alkyl groups to an extent such that this heavy alkyl (wax) substituent comprises a sufficient proportion of the composition as a whole to render the same oil-miscible so that it will form a mineral oil solution or colloidal suspension which will remain stable as such under normal conditions of handling and use. It appears that there is a critical range in the degree of waxsubstitution below which these wax"- substituted compounds will not satisfy the requirements for oil-miscibility.

The critical range in the degree of wax-substitution of the aryl nucleus in the preferred compounds contemplated herein may vary with: (a) the mineral oil fraction in which the compound is used: (b) whether the arylnucleus is monoor po ycyclic or monoor polyhydric: (c)

monoor polysubstitution of the aryl nucleus with heavy alkyl groups; and (d) other substituents on the nucleus which may be of positive or negative or of neutral oil-solubilizing activity;

Inview of theforegoing variables it would be impracticable and probably misleading to attemptv to give an expression and figure which would. indicate accurately the proper ratio of hydroxy-aromatic constituent to the "wax"-substituted hydroxyaromatic constituent in the starting material which would satisfy all cases taking assaults l Y these variables into account. As a guide for preparing these preferred compounds, however, our research indicates in general the ratio, expressed as weight of hydroxyaromatic component in the product to the corresponding wax-substituted hydroxyaromatic nucleus or component therein, should not be greater than about seventeen parts .by weight of the former to about 100 parts by weight of the latter, or about 17 per cent, when p the hydroxyaromatic component is expressed in It is again pointed out that the condensed sulfur derivatives or sulfides of the alkylated acylated hydroxyaromatic compounds are the preferred class of addition agents contemplated herein. For that reason and for the sake of simplicity the invention, with special reference to methods of preparation of the compositions involved, is hereinafter specifically described with reference to the sulfides, but it is to be understood that the corresponding selenides and tellurides are contemplated by and come within the scope of'the broad invention.

One general procedure for synthesizing the monoand poly-sulfides of the acylated alkylsubstituted hydroxyaromatic compounds of the type contemplated herein involves the condensation of the corresponding alkylated hydroxyaromatic compounds with sulfur or sulfur halides, followed by the acylation of the hydroxyl group. In the above general procedure an alkali or alkaline earth metal oxide or metal phenate of the alkyl-substituted hydroxyaromatic compounds preferably the corresponding sodium phenate,

may be employed as the starting material in place of the free phenol as will be more fully explained further on in connection with a specific example of this general method. In the event sulfur dichloride (SCh) is used in the general procedure described above, the condensation product will be in the nature of a monosulflde (or a condensate or polymer thereof); sulfur monochloride (SzClz) will yield the corresponding disulflde (or a condensate or polymer thereof) and, of course, a mixture of sulfur halides may be employed to yield a mixture of'such sulfides. Elementary sulfur may be employed as the condensation reagent, but this is not considered the most desirable procedure.

Sulfur derivatives of higher sulfur content may be obtained by reacting a compound havinga disulfide' linkage (obtained with sulfur monochloride)" with sulfur or with alkali. polysulfides or with an alkyl tetrasulfide..8uch higher sulfur derivatives may also be obtained by first reducing the disulflde to form an aryl mercaptan or thio-phenol of the alleviated hydroxyaromatic compounds (or alkali metal phenate) and then reacting the thio-phenol or phenate with sulfur dichlorlde (to form the trisulflde) or with sulfur monochloride (to form the tetrasulfide) of the .alkylated hydroxyaromatic. compound (or alkali metal oxide or metal phenate thereof), which.

can then be acylate'd to form the polysulfide of the corresponding explained above.

The alkylated hydroxyaromatic compounds (or. alkali or alkaline earth metal oxide or metal.

phenate'thereof). used in the above general.procedure in preparingthe sulfides of the corresponding acylated derivatives may be obtained in various ways. For example, a hydroxyaromatic compound such as alkyl group or groups. This alkvlatedhydroxyaromatic compound may then be. used directly as the starting material or first converted into an alkali or alkalineearth metal oxide or metal phenate which may also be employed as th start ing material, as explained above.

The alkylation of the hydroxyaromatic compound ma be carried out in various ways. A preferred procedure is to subject a hydroxyaromatic compound to a Friedel-Crafts condensation reaction with a halogenated aliphatic hydrocarbon containing at least twenty carbon atoms or with halogenated petroleum wax. Mixed alkyl Y or aralkyl aryl ethers may also be used in the formation of alkylated hydroxyaromatic compounds by the Friedel-Crafts reaction, rearrangement of the alkyl or aralkyl ether radical taking place to give the phenolic OH group. This alkylation may also be can'ied out with an unsaturated aliphatic hydrocarbon or with aliphatic alcohols, using anhydrous aluminum chloride as.

a catalyst. For obtaining the preferred multifunctional addition agents for mineral oils the unsaturated hydrocarbons in aliphatic alcohols should be high molecular weight compounds containing at least twenty carbon atoms such, for example, as eicosylene, cerotene, melene, polymerized isobutylene, etc., or myricyl alcohol, ceryl alcohol, etc.

The Friedel-Crafts synthesis is preferred for obtaining the alkylated hydroxyaromatic compound, and as a source of the alkyl substituent preference is given to mixed high molecular weight hydrocarbons typified by those which characterize the heavier products of petroleum,

such as heavy petroleum oils of the lubricant typ petrolatum and crystalline petroleum wax or other compounds which will result in relatively long chain aliphatic substituents. Special,

preference is given to petroleum wax of melting point not substantially less than about 120 E,

which is predominantly characterized by aliphatic, hydrocarbons having a molecular weight of about i 350 and containing at least twent carbon atoms. Hydroxyaromatic compounds which may be I used in the alkylation reaction are:. monoor poly-cyclic and monoor poly-hydrlc hydroxyaromatic compounds which may or may not be otherwise substituted, as hereinafter indicated.

Specific examples of compounds which may be used in this reaction are: phenol, resorcinol, hydroquinone, catechol, cresol, xylenol, hydroxydiphenyl, benzyl phenol, phenylethyl phenol, phenol acyloxyaromatic compounds as phenol or naphthol ma first be alkylated to substitute part of the nuclear hydrogen with a heavy 20 carbon atom or waxresins, methylhydroxydiphenyl, alpha and beta naphthol, xylyl naphthol, benzyl phenol, anthra nol, phenylmethyl naphthol, phenanthrol, anisole,

beta naphthyl methyl ether, chlorphenol, and the like. Preference in general is to the monohy droxy phenols otherwise unsubstituted, particular preference being given to phenol and alpha and benzoic and naphthoic acids.

art and it has now been discovered that they are v also applicable to the more complex hydroxyaromatic compounds employed in making the compositions of the present invention. It should also be pointed out that where nuclear substituents are present containing methylene groups such as alkyl, keto, ether, ester radicals, etc., the same may also carry substituents such as halogen, cyano, nitro, and thio groups. The general methods for introducing these groups into such nuclear substituents in the case of simpler compounds are well known to those skilled in the art and have also been found to be applicable here.

In the event it is desired to produce a product which contain an alkoxy or aroxy group as a" cohol, ceryl alcohol, etc.), using H2304 as a catalyst. By this procedure the hydroxyaromatic ether can be alkylated without substantial rear-' rangement taking place. As an alternative procedure, polyhydric phenols can be alkylated with higher alcohols or high molecular weight aliphatics or by Friedel-Crafts reaction, followed by substitution of one hydroxyl hydrogen with a low molecular weight alkyl group, which substitution can be effected by treating the alkylated polyhydric phenol with an alkali alcoholate to substitute an OH group with alkali metal and then treating with the desired alkyl halide whereby the substitution is effected.

When it is desired to obtain a nitro or amino substituent, the aryl hydroxide ,is alkylated or wax-substituted when free of such substituent.

This i followed by nitration to introduce the nitro group. The amino group can be obtained by reduction of the nitro group.

Examples of acyl chlorides of the inorganic acids of non-metallic or acidic metalloid elements that may be used in the .acylation reaction mentioned above are I the following: P0013,

PSC13, BC13, SiCl4,'PCls, PCls, as well as the corresponding bromides and iodides.

Representative examples of theorganic acid anhydrides or acyl halides which may be used for this purpose are the anhydrides or acyl halides of the following organic acids:

(1) Saturated aliphatic mono acids ranging from acetic to montanic acid.

(2) Unsaturated aliphatic monocarboxylic acids such as acrylic, oleic, elaidic, crotonic, etc.

* carboxylic (3) Saturated aliphatic polycarboxylic acids such as succinic, oxalic, adipic, sebacic,'etc.

(4) Unsaturated aliphatic polycarboxylic acids such as maleic and fumeric acids. 7

(5) Substituted mono and polycarboxylic aliphatic acids containing halogen, hydroxyl, amino, ether or keto groups such as chloracetic acid. hydroxystearic acid, tartaric acid, glycollic acid, octyloxyacetic acid and pyroracemic acid. (6) Aromatic monocarboxylic acids such as (7) Aromatic polycarboxylic acids such as phthalic acid.

(8) Alkylene-substituted aromatic monocarboxylic acids such as cinnamic acid.

(9). Aryl-substituted mono and polycarboxylic aliphatic acids with carboxyl in the side chain such as phenylstearic, naphthyl stearic and naphthyl polystearic acids.

' (10) Substituted aromatic mono and polycarboxylic acids containing halogen, hydr'oxyl, amino, alkyl, aryl, aralkyl, keto, nitro or alkoxy in the nucleus, such as chlorbenzoic, salicylic, anthranilic, toluic, phenyl-benzoic, benzoylbenzoic, nitro-benzoic, and anisic acid.

' (11) Non benzenoid cyclic mono and polycar boxylic, acids such as abietic and camphoric acids, and heterocyclic carboxylic acids such as furoic acid. 1

0f the above organic acylating agents, those corresponding to the saturated aliphatic and aromatic acids are preferred. In most cases, compounds which impart higher V. I. to mineral oils can be prepared by use of the dibasic acid chlorides because of the formation of more resinous products thereby.

To illustrate the procedure which may be followed in preparing the compositions contemplated by this invention, I will now describe the various steps which may be followed in synthesizing the monosulfide or the disulflde of the phosphite ester (acyl) of wax-phenol.

By the term wax in this connection I mean, a previously indicated, a mixture of higher aliphatic radicals or groups corresponding to the higher aliphatic hydrocarbons which characterize petroleum wax, the resulting product being, therefore, a mixture of the sulfides (monoor di-) of the corresponding nuclear alkyl-substituted phosphite esters of phenol.

The procedure to be followed in preparing other esters, other polysulfides and other condensation products such as selenides and tellurides, containing other alkyl substituent than those derived from petroleum wax and other aryl nuclei than that characterizing phenol will be obvious from the following description in the light of the foregoing.

The following description also illustrates the procedure which may be followed in making those compounds which are preferred for their multifunctional oil-improving properties. As will be apparent to those skilled in the art, compounds or compositions having a combined phenol content in excess of that necessary for oil-miscibility may be readily obtained by using a chlorinated Wax having a chlorine content substantially higher than that given in the example below or by changing the ratio of the reactants (chlorwax and phenolic compound).

ALKYLATION OF PHENOL A paraffin wax melting at approximately F. and predominantly comprised of aliphatic compounds having at least 20 carbon atoms in their molecules is heated to about 200 1"., after which chlorine is bubbled therethrough until the wax has absorbed about per cent to about 16 per cent of chlorine, such product having an average compositionbetween that corresponding to a monochlor-wax and a dichlor-wax. A quantity or chlor-wax thus obtained containing 3 atomic proportions of chlorine is heated to a temperature varying from Just above its melting point to not over 150 F., and 1 mol of phenol (hydroxybenzene) i admixed therewith. The mixture is heated to about 150 F., and a quantity of anhydrous aluminum chloride corresponding to about 3 per cent of the weight of the chlor-wax in the mixture is slowly added with active stirrin The rate of addition of the aluminum chloride should be sufiiciently slow to avoid violent foaming, and during such addi-- tion the temperature is preferably held at about 150 F.; after the aluminum chloride has been added, the temperature of the mixture may be increased slowly to control the evolution of HCl 88's to a temperature of from 250 F. to 300-350? F. If the emission of 1101 gas has not ceased when the final temperature is reached, the mixture may be held at 330 F. for a short time to allow completion of the reaction, but to avoid possible cracking of the wax the mixture should not be heated appreciably above 350 F., nor should it be held at that temperature for any extended length oi time. Removal of non-alkylated material (phenol) can be effected generally by water-washing, bptfit is preferable to treat the water-washed product with super-heated steam, thereby insuring complete removal of the unreacted material and accomplishing the drying of the product in the same operation.

A wax-substituted phenol prepared according to the above procedure in which a quantity of chlor-wax containing 3 atomic proportions of chlorine (16 per cent chlorine in the chlor-wax) is reacted with 1 molecular proportion of phenol, may for brevity herein be designated as "waxphenol (3-16). Parenthetical expressions of the type (A-B) will be used hereinafter in connection with the alkylated hydroxyaromatic compounds to designate (A) the number of atomic proportions of chlorine in the chloraliphatic material reacted with one mol of aromatic compound in the Friedel-Crafts reaction and (B) the percentage of chlorine in the chloraliphatic material. In the above example, A=3 and B=16. The same designation will also apply to the sulfides of the wax-substituted acylated hydroxyaromatic compounds which constitute the ultimate product derived from the waxphenol.

In forming the alkali metal phenate of a waxphenol of the type obtained by the procedure described above, as an alternative starting material, a preferred method involves the substitution of the phenolic hydrogen with finely divided alkali metal. Because of the high viscosity of the mixtures it is advantageous to dilute the wax-phenol initially with from one to three parts of heavy mineral oil, in which case the finished product is a concentrated mineral oil blend. By the use of mineral oil diluent, wax phenols of higher phenol content can be used in the formation of products of this invention. The formation of a wax-alkali-metal-phenate, for example, may be carried out by diluting 500 parts by weight of wax-phenol obtained according to the foregoing procedure, with 1500 parts by weight of mineral oil of Saybolt viscosity of about 60 1 aliphatic alcohols are usually the most suitable;

and as an example, 500 parts by weight of waxphenol (3-16) was reacted with 16 parts by weight sodium in the forms of ethyl or butyl sodium oxide by heating the mixture toabout 300 F. during about a one-hour period and allowing the alcohol released in the reaction to distill oil.

The product of this step is the sodium phenate of wax-substituted phenol (3-16); or in case mineral oil is used as diluent, it is a mineral oil solution of such phenate having a gelatinous ICOIlSiSiSGIL'Y. In the absence of'diluent, the waxsodium phenate is a waxy product.

This metal phenate may be converted, if desired, to the corresponding phenol by neutralization with a mineral. acid.

FORMATION OF THE SULFIDES OF WAX-PHENOL The sulfides o1 wax-phenol may be obtained by first dissolving the wax-phenol in a suitable solvent such as carbon disulfide, benzene, chlorbenzene, ethylene dichloride, Stoddard solvent, or the like, and bringing the temperature of the solution up to about R, which is followed by addition of a sulfur halide (monoor di-) or mixture of sulfur halides during about a V2 hour period. The mixture may then be held at this temperature for about one hour to complete the formation of. the sulfide derivatives. HCl is evolved in the reaction; resulting in fixation of the sulfur in the aryl nucleus. As regards the temperature of the reaction, it is to be understood that the reaction can be carried out at various temperatures from room temperature up to the boiling point of the solvent, but it.is preferable for obtaining light-colored products that the temperature be not too high. The addition of the sulfur halide is controlled so as to prevent over-heating of the mixture by its heat of reaction. This mixture, i then water-washed to remove dissolved hydrochloric acid, and the free phenol may be acylated as hereinafter described, or if desired it may be acylated after conversion to the corresponding alkali phenate type compound, in which case free H01 is not evolved, unless an amount of sulfur halide in excess of the alkali metal content is used, the H61 being converted to alkali metal chloride by reaction with the alkali-phenate. When the alkaliphenate is reacted in the manner just described, solvents such as carbon disulfide and ethylene dichloride must be replaced with solvents such as alcohol, benzene, or chlorbenzene to avoid side reactions with the alkali derivative.

The following example illustrates a preferred method of preparing the phosphite ester (acyl) of wax-phenol disulfide which is one of the preferred oil-improving agents of the present invention. It is to be understood, however, that my invention is not limited to the details of this specific example which is given merely by way of illustration and from which, taken in connection with the explanations and descriptions given above. he various other procedures and methods which may be followed for making this same product and for making the various other products comprised by the present invention will be apparent to those skilled in the art.

ExAMPLa Preparation of the phosphite ester (acyl) of was:-

phenol disulphide Reaction mixture:

Wax-phenol disulflde .mol..- l

The wax-phenol sulfide is dissolved in the ethylene dichloride in a flask equipped with stirrer and reflux condenser and brought to a temperature of about 150 F., followed by addition of the P613. The mixture is then refluxed about one hour to complete the reaction, followed by water washing the mixture and distilling the solvent to obtain the finished product.

The reaction can be carried out also by double decomposition of an alkali phenate sulfide with the inorganic halide. This procedure is used in the preparation of inorganic ester derivatives from less reactive halides such as B013. In this case the ethylene dichloride is replaced by a diluent which is unreactive with the alkali salt,

such as chlorbenzene or a mineral oil solvent.

The procedure to be followed in obtaining the corresponding disulfides or esters (acyls) other p than the phosphite ester will be readily apparent from the foregoing to those skilled in the art, as will also the variations in the procedure with mineral oil fractions in minor amounts from about per cent to 10 per cent to obtain min-f eral oil blends of improved pour point and viscosity index, such oils being thereby also stabllized against those deleterious effects of oxidation which, for example, are manifested in an internal combustion engine by the formation of sludge, acid, and by the formation of lacquer.

aseaaes These 011 blends, in addition its being of improved pour point and viscosity en, therefore. may be used in internal combustion engines and under the conditions of use encountered therein produce a marked decrease in the tendency to form acid and sludge and a further marked decrease in the tendency to cause piston sticking and the filling of the slots in the oil rings with a deposit.

The wax-substituted compositions of the present invention obtained by the exemplary procedures described above are, as the result of their relatively low phenolic ratio or combined phenol content, all oil-miscible or oil-soluble product's. Although products of this type are designated herein as preferred because of their multifunctional oil-improving properties, it is again emphasized that the invention is not limited to these oil-miscible wax-substituted compositions but is inclusive of this entire held of products irrespective of oil-miscibility.

Compounds or compositions of both the oilmiscible and non-miscible types have beenprepared, and of the oil-miscible products synthesized all have been tested as additive agents for viscous mineral oils andhave been foundto be Phosphite ester of wax phenol disulfldeu. (3-16) Silicon ester of wax phenol disu1flde--- (3-16) Thiophosphate ester of wax phenol disulfide (3l6) Phosphite ester of wax alplha naphthol 'disulfide (3-15) This application is a continuation in part of my copendlng application Serial Number 331,230,

filed April 23, 1940.

I claim: The phosphite sulfide.

ester of paramn-wax-phenol di ORLAND M. REIFF. 

